<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Sample Layout</title>
    <link rel="stylesheet" href="layout.css">
</head>
<body>
    <header>HEADER</header>
    <section id="wrapper">
        <div id="content-area">CONTENT</div>
        <div id="left-side">LEFT SIDE</div>
        <div id="right-side">RIGHT SIDE</div>
    </section>
    <footer>FOOTER</footer>
</body>
</html>
